J. Thewalt Lab

Needle in a hay stack cartoon


Click on one of the links below to read about our projects.

Fluorescent Probes


Lipid Rafts

Cell Death Lipids

List of Publications

Fluorescent Probes

Other groups use fluorescence techniques and electron spin resonance spectroscopy (ESR) to study phase behavior of lipids. These techniques require the use of a minuscule amount of fluorescent probe or spin label, which was thought not to alter membrane phase behavior. Several groups have begun to question this assumption.

We found that 0.05 mol% of the probe DiIC12 is enough to significantly alter the temperature at which the liquid ordered (lo) and liquid disordered (ld) phases mix in membranes of 1:1 DOPC:DPPC-D62 + 30% cholesterol (Tmix). In fact, 0.5 mol% DiIC12 raised Tmix by an astonishing 6°C. We are now studying the effects of the probes Laurdan and Naphthropyrene on phase transition temperatures.

DiIC12 concentration dependence of Tmix

Veatch, S.L., Leung, S.S.W., Hancock, B., Thewalt, J. (2007) Fluorescent probes alter miscibility phase boundaries in ternary vesicles. J. Phys. Chem. B. 111:502-504.

2014 poster

Sherry Leung's PhD Thesis